Gases Emissions during Composting Process of Agri-Food Industry Waste

The vegetable production is an important part of agriculture sector in every country. In Poland, vegetables and fruits production covering the area of no more than 3% of agricultural land, is more than 36% of plant production and 14-15% of the whole agricultural production. The study aim was to determine the management possibilities of the selected waste from vegetable production in composting process. Laboratory tests were carried out using the bioreactor set-up with capacity of 165 dm(3), respectively, for each chamber. The composting process has been tested for the following mixtures: K1-cabbage leaves, tomato dry leaves + manure and slurry additive; K2-cabbage leaves, solid fraction from biogas plant + manure and straw additive; K3-cabbage leaves, onion husk + straw additive. In all three composts the thermophilic phase occurred which indicates that the process ran correctly. In each chamber, the temperature exceeded 70 degrees C and its maximum value during the experiment was 77.5 degrees C for K2 compost. The article discusses changes in O-2, CO2, NH3 and H2S emissions during composting. The carbon dioxide concentration in the exhausted gas from analyzed composts and the ratio with oxygen they testify to the decomposition of raw materials in the composting process. The results showed that the agri-food waste can be a proper substrate for composting production. Due to legal regulations and the increase in prices of mineral fertilizers, the development of the compost market should be expected.